Aside from the new interface, which borrows heavily from iOS 7, Macs, iPhones and iPads can now work and play a lot more happily.

For example, once you've installed Yosemite (due later this year), your Mac can act as a speakerphone, and Messages now handles SMS. And the wireless file-sharing tool Airdrop will be extended to include Mac as well.

Giving Mac, iPhones and iPads a more similar interface, and more crossover tools, will help the so-called "halo effect" whereby happy iOS device users grade in their Windows PC for an Apple laptop or desktop.

Cloud storage gets a big boost — and Windows support
Apple also used the WWDC to announce iCloud is being pepped up to iCloud Drive (which will work with Yosemite and iOS 8 (below).

Free online storage is still a lousy 5GB, but you will be able to add 20GB for $US0.99, and 200GB for $US3.99 a month, with tiers up to 1 terabyte.

iCloud Drive will also work with Windows, Apple says — shaping it up to be a major threat to the likes of Dropbox.

OS X Yosemite was released to third-party software developers today. The final version is expected in Spring.

We've already seen a price war on the corporate side of cloud computing. It's encouraging to see hostilities brewing on the consumer side with storage and other elements.

Coming in iOS 8
A preview of iOS 8 revealed the next upgrade to Apple's iPhone, iPad and iPod Touch software will include a smarter Siri.

Simply saying "Hi Siri" will activate the voice software.

Siri also gains the ability to recognise songs, a la Shazam.

iOS 8 will also let you respond to messages, or "like" Facebook posts from your iPhone or iPad's lockscreen (there's also the US-centric ability to bid on eBay auctions from the lockscreen).

It's also worth highlighting, amid a blizzard of new features that Messages gets audio and video — putting it squarely in competition with recent Facebook acquisition WhatsApp (or maybe not squarely, given it's confined to the iOS universe). This is a development phone companies will watch with concern.

The number of third-party apps under competitive pressure mounted as Apple's San Francisco presentation went on.

Others include Snapchat — by dint of iOS 8's new self-destructing message feature, and Swyft, from a new iOS keyboard option called QuickType. On the plus side for developers, iOS8 will support third-party keyboards for the first time.

iOS 8 will also get more photo editing features, plus the ability to sync edits across many devices.

Also on the horizon are video previews of apps on Apple's AppStore, and the ability to buy bundles of apps for a discount.

At WWDC 2013, developer were wary after a keynote address that unveiled iOS 7, with its radical new look. Response was a little on the muted side.

This year's keynote sent the crowd into a social media frenzy — and in my feed at least, it was wall-to-wall positive.